Extracellular Vesicles in HIV, Drug Abuse, and Drug Delivery.

Extracellular vesicles (EVs) are known to perform important biological functions and have been implicated in multiple disease pathogeneses, including HIV and drugs of abuse. EVs can carry biological molecules via biofluids such as plasma and cerebrospinal fluids (CSF) from healthy or disease organs to distant organs and deliver biomolecules to recipient cells that subsequently alter the physiology of the recipient organs. As biocarriers, EVs have the potential to be developed as non-invasive biomarkers for disease pathogenesis and drug abuse, as the level of specific EV components can be altered under disease/drug abuse conditions. Since many drugs don't cross the blood-brain barrier, EVs have shown the potential to encapsulate small drug molecules, including nucleotides, and carry these drugs to brain cells and enhance brain drug bioavailability. Through this special issue, we have covered several studies related to the role of EVs in altering biological functions via cell-cell interactions in healthy, HIV, and drug of abuse conditions. We have also included studies on the role of EVs as potential biomarkers for HIV pathogenesis and drugs of abuse. Further, the potential role of EVs in drug delivery in the CNS for diseases, including HIV-associated neurocognitive disorders and other neurological disorders, are covered in this issue.